When Tuberculosis Meets The Spine: The Legacy of Percivall Pott

You receive a call from the neurosurgery intern who is frantic! He states that he is in desperate need of your help. Mr. DU is a 54 yo M who presented from home with “weak” legs and difficulty walking. The intern is panicking because he thinks the patient might have cauda equina syndrome, but it is hard to determine because the he has had saddle anesthesia and incontinence for many years stemming from a case of Fournier gangrene. Also, with his history of DM, HLD, and HTN many of his symptoms could also be vascular disease. A lumbar CT is negative and you agree to the mandatory neuro-checks and admit him to the unit. The initial neuro exam shows an underwhelming amount of weakness with ambulation.

The next morning you go over the MRI and find only a strange lesion in the thoracic spine:

When you freeze the image you see something suspicious in the region of T8-T9…

A re-examination shows increased weakness to the lower extremities as well as significant pain over the lower thoracic region. You go to the eMAR to write the order for empiric antibiotics and you see a peculiar test ordered by the neurosurgery intern:

QuantiFERON®-TB Gold: Positive

When asked, he states that the pt was recently incarcerated and he remembers that inmates get Tb (it was on step 2)

A frantic recheck of his CXR shows:

A million questions enter your head: Do you start isolation? What anti-tuberculosis medications do you need? how sensitive is QuantiFERON®-TB Gold?

The big question still looms: What you are you going to do?

Background:

Tuberculosis (Tb) of the spine (Pott’s disease) accounts for about 2% of all cases of Tb and 10% of extrapulmonary Tb

Typically involves 2 adjacent vertebral bodies with anterior wedging (due to disproportionate destruction of the anterior aspects of the vertebral bodies) and narrowing of the intervertebral disk space

Pts will often experience months of spinal or radicular back pain before presentation

Only 67% will have pulmonary Tb (the only Tb disease requiring drop-let isolation)